Syringe.



No. 792,299. PATENTED JUNE 13, 1905.

S. M. WEAVER. f

SYRINGB.

APPLIOATION FILED AUG. 27. 1904.

MTN/S5555 f/YVEHTOR i @www if@ Mumfl WMOMU Wm Patented June 13, 1905.

PATENT OFFICE.

SAMUEL M. IVEAVER, OF CLEVELAND, OHIO.

SYRINGE.

SPECIFICATION forming part of Letters Patent No. 792,299, dated June 13,1905.

Application iiled August 27, 1904. Serial No. 222,414.

To @ZZ r11/1,0711, 'it mfr/y concern:

Be it known that I, SAMUEL M. WEAVER, a citizen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented a certain new and useful Improvement in Syringes, of which thefollowing is a full, clear, and exact description, referencebeing had tothe accom panying d rawings.

Broadly speaking', this invention relates to syringes of a type whereina plunger is utilized in connection with a cooperating cylinder, wherebythe liquid previously drawn into the cylinder is forced out by theplunger. More specifically, however, the invention relates to syringesfor use in dentistry, whereby cocaine or other anesthetic is forcedLinder pressure into the pores of the tooth itself, thus deadening thenerves and obviating all pain to the patient. In instruments of this-type it is necessary that the plunger should be capable of being drawnout in order to fill the c vlinder with the anesthetic, and after it isso lilled and the point placed in the cavity in the tooth the plungermay be forced up to till the cavity or other-parts of the tooth to beoperated upon, and, finally, after the liquid has been cushioned by thefollowing up of the plunger to till the parts in the manner describedthat additional force may be applied to the plunger to further force andcompress the liquid and till all of the pores of the tooth, so that thenerves about the cavity or the part to be operated upon may betemporarily deadened, and thus do away with any pain to the patient.

The invention may be further briefly summarized as consisting in theconstruction and combination of parts hereinafter described, referencebeing' had to the accompanying specification, drawings, and claims.

Referring to the drawings, Figure 1 is a side elevation, partly insection, showing the general arrangement of the instrument, togetherwith its internal operating mechanism. Fig'. 2 is a section upon line 22 of Fig. l looking' toward the right. Fig. 3 is a section upon line 3 3of Fig. l looking' toward the left, and

Eig. L is a side elevation showing' the connection of the iingeroperating-lever with the device, and Eig. 5 is adetailed view of thepoint.

Any preferred form of syringe may be provided with my improved form ofhigh-compression mechanism; but I prefer to utilize the construction setforth in the drawings, wherein- A represents a cylinder provided at oneend with a threaded portion adapted to receive the point and at itsopposite end with screw-threads a', adapted to receive the end of thesleeve B, which in turn is provided with internal threads 7) at itsopposite end for receiving' the threaded portion of a glandring having atapering inner end, as shown at 52. The inner end of the cylinder A istapered also, as at a2, to correspond with the taper b2, whereby packingb3 is firmly seated within the sleeve B for making a seal between theplunger and the sleeve to prevent the leakage of the anesthetic or otherliquid through the back end of the cylinder. The gland-ring is providedwith radial notches for a purpose which will be described. Within thepacking and within the gland-ring Z2' slides a plunger C, which titssnugly within these parts, so as to prevent an unnecessary amount ofleakage between it and the cylinder. Outside of the gland-ring theplunger is provided with a pin c, extending through the plunger andadapted when the plunger is pushed in to its extreme position to haveits ends engage in the radial notches 6*, whereby the plunger may berotated and the gland-ring unscrewed from the sleeve B for the purposeof renewing the packing or adjusting any of the parts. The plunger C isfurther provided upon its outer end with a socket 0, provided with aknurled periphery c2 for the purpose of rotating the plunger. In thissocket is a rubber handpiece c, made to fit within the hollow of thehand and to prevent injury to it.

So far the description has been confined to the construction of thesyringe proper, and these parts are more or less of general constructionand operation; but the description will now be conlined to those partswhich substantially belong to my invention and which constitute what maybe termed the highpressure mechanism.

Secured to the cylinder A by means of a collar (Z engaging the threads aupon the cylinder and between it and the end of the sleeve B is a fingerguard member D. This member is rigidly held in place by the collar Z andis provided withlongitudinal arc-shaped grooves d', as shown in Fig. 1and in dotted lines in Fig. 2, for guiding the racks to be described.Extending laterally from this member D are the finger-guards (Z2, ofsuitable shape to conform to the backs of the lingers and are arrangedwith respect to the barrel so that they, together with the handpicce c,will furnish suitable means for manipulating the syringe in the patientsmouth. The guard member D is further provided with trunnions or pins d,to which is pivoted the linger operatinglever E. This lever is providedwith lingerpieces e of suitable size and conlie'uration to conform tothe inner side of the lingers and is arranged'in close proximity to theguard linger-pieces d2, so that after manipulating' the syringe withinthe mouth of the patient and.

in position for operation upon the tooth the operators lingers whichhave adjusted the instrument may be moved back and forth against thelever in a manner to be described, and the additional high pressure willbe exerted upon the liquid. This lever is provided with a centralopening for the passage of all the parts associated with the cylinderand the sleeve B, and in its recess is pivoted a pair of pawls c',adapted for engagement with a pair of racks f, having a headf', providedwith an openingthrough which passes the plunger C. The head may be slidso as to engage the pin c, passing through the plunger, whereby upon theshifting of the lever E these pawls will take into the teeth of theirrespective racks and will step by step move the plunger forward andcompress the liquid anesthetic through the point of the syringe. Thesprings einormally press these pawls into engagement with their racks.The racks f are substantially of the form shown in cross-section in Fig.3, with the teeth milled across their outer arcshaped periphery and withtheir inner surfaces taking snugly against the sleeve B and their outerperiphery against the guard member D and within the arc-shaped recessestherein. The crescent shape of these racks provides a suitable meanswhereby they are guided between the sleeve B and the guard member, sothat there is no straining on their connecting-head j". Suitable meansis provided for moving these pawls out of engagement with theirrespective racks. This mechanism consists of a bearing-ring G, securedto the shoulders c upon the lever E and has an annular recess (y thereinfor receiving an annular llange 7l. of a cam-ring H. This eamring has aknurled periphery /z/ and is provided with cam-surfaces it, which arearranged to take against the tails e" of the pawls and move their pointsout of engagement with the teeth of their respective racks. The cam-ringH is further provided with slots L, through which pins 71,Al pass forsecuring it to the bearing- 1ing.

Upon the forward end of the cylinder A and upon the threaded shank L issecured the point J, having a threaded socketly', adapted to screw uponthe Shanks a. This point is provided with a long steel central tube y",having an outer casing or coating/2, of soft solder, tin, or othersuitable sealing material, whereby upon the insertion of the point intoa cavity this solder or sealing material will permit the tooth portionsto embed themselves therein, and thus prevent the leakage of the liquidanesthetic at that point. A jacket j may be provided around the casingor coating of soft solder, tin, or other suitable material to hold it inshape and prevent backing up when the instrument is inserted into thecavity.

A complete description will now be given of the operation of theinstrument. The operator places the point into the cavity and pressesagainst the linger-guards fl with the backs of his lingers until thesoft coating' upon the point has seated itself lirml y in the cavity andthere is no opportunity for leakage at that point. Then the palm of thehand is brought to bear against the hand portion c and the liquidanesthetic which has been drawn into the cylinder previous to placingthe instrument into the patients mouth is forced into the cavity by theplunger moving' into the cylinder. The head f, with the racksf, is thenmoved up until it engages the ends of the pin c passing through theplunger, this moving' up of the head being accomplished either bypushing upon it with the lingers or by moving the two lingers which havebeen in engagement with the guardpieces (Z2 back against theoi'ieral'ing-lever, operating it with the lingers and through the Y)awls e' e shiftinea and through the racks until such engagement isbrought about. After the head f is brought into engagement with the pinthen the compressing operation takes place--that is, the lingers inengagement with the linger-pieces c are drawn back or doubled upalternately, thus shifting the lever E upon its pivot and bringing thepawls into engagement with their racks, one holding while the othermoves back to take a fresh hold upon the teeth, and thus drawing uponthe plunger and compressing' the liquid into the cavity. It will be seenfrom the arrangement of lever E and the pawls, together with theirracks, that any amount of compression may be had in the cylinder withinthe capacity of the instrument, and after such compression is attainedthe operating-lever may be left in IOO IIO

a state of rest and the compression held for any length of time withoutany strain upon the lingers or hand, with the exception of the holdingof the palm against the handpiece c to hold the instrument in place, andthis need only be suilicient to prevent leakage between the point andthe tooth. To release the plunger, the cam-ring /t' is rotated so as tobring' the Cain-surfaces it? into engagement with the tails eof thepawls, whereby their forward ends or parts are drawn out of engagementwith their respective racks, thus permitting the racks to slide backthrough the reaction of the compression upon the plunger.

Having described my invention, I claim-- l. In a syringe, incombination, a relatively movable cylinder and plunger, andratchetand-pawl mechanism independent of but adapted to cooperate withsaid plunger to operate against the liquid and compress it in thecylinder.

2. In a syringe, in combination, a cylinder and plunger carried thereby,a member telescoping onto said cylinder and having' a part adapted toengage a part of said plunger, and means for giving said member astep-by-step movement whereby it will move the plunger and compress theliquid in the cylinder.

3. In a syringe, in combination, a cylinder and cooperating plunger, aprojection carried by said plunger, a member adapted to slide on saidcylinder and having a head for eng'aging' said projection on saidplunger, a lingerlever for moving said sliding member to bring said headinto engagement with said projection and move said plunger.

4. In a syringe, in combination, a cylinder and eoperating plunger, aprojection carried by said plunger, a member adapted to slide on saidcylinder and have a part engage said projection, racks provided uponsaid member, and lever-and-pawl mechanism for engaging said racks tomove said member.

5. In a syringe, in combination, a cylinder, a plunger' therefor, aprojection carried by said plunger', a member slidable upon saidcylinder and having a portion thereof for engaging said projection, afinger-lever pivoted to the cylinder racks carried by said slidablemember, and pawls carried by said lever for engaging' said racks to setup said plunger and compress the iiuid in the cylinder.

6. In a syringe, in combination, a cylinder, a plunger, a rack slidableupon said cylinder and having a portion adapted for engagement with saidplunger, and an operating-lever suitably pivoted and provided with apawl for engaging said rack.

7. In a syringe, in combination, a cylinder', a plunger, a projectioncarried by said plunger, a pair of racks, slidably mounted upon saidcylinder, a head connecting said racks and adapted to engage saidprojection on the plunger, a finger-lever having portions eX- drawingsaid pawls from their engagement with said racks.

9. In a syringe, in combination, a cylinder, a plunger, a projectioncarried by said plunger, a pair of racks slidably mounted upon saidcylinder, a head connecting said' racks and adapted to engage saidprojection on the plunger, a linger-lever pivoted to said cylinder andhaving linger portions extending from either side of said cylinder,pawls carried by said lever for engaging said racks, and a camring forengaging said pawls to disengage them from the racks.

10. 'In a syringe, in combination, a cylinder, a finger-guard rigidtherewith, a pair of racks slidably mounted in said linger-guard andupon the outside of said cylinder a head connecting said racks, aprojection upon the plunger adapted to be engaged by said head, aiinger-lever pivoted to said linger-guard, and pawls pivoted in saidlinger-lever for engagement with said pawls.

l1. In a syringe, in combination, a cylinder, a sleeve rigid with saidcylinder, a glandring carried by said sleeve, a plunger extendingthrough said gland-ring', into said cylinder, a pair of racks slidableupon said sleeve, a head connecting said racks and surrounding saidplunger, a pin passing through said plunger for engagement with saidhead, a finger guard member having' suitable recesses for receiving saidracks, and a linger-lever pivoted to said guard member and carrying apair of pawls for engagement with said racks.

l2. In a syringe, in combination, a cylinder, a plunger, therefor, racksfor moving said plunger into said cylinder, a linger-lever pivoted tosaid cylinder, pawls carried by said lever for engagement with saidracks, and a cam-ring rotatably mounted upon said lingerlever forengaging said pawls and moving them out of eng'agment with said racks.

13. In a syringe, in combination, a cylinder, a plunger therefor, racksfor moving said plunger into said cylinder, a linger-lever pivoted tosaid cylinder, pawls carried by said cylinder for engagement with saidracks, and bearing-ring rigidly mounted upon said lever and a cam-ringrotatably mounted in said bearing-ring for engaging said pawls andmoving them out of engagement with their racks.

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14. A point AFor a syringe having` a central tubular portion and acasing` therefor of soft metal.

15. ln a device for coinpressing` a liquid into a tooth. the combinationwith compressing means, et' a point having` a tubular center with acoatimrgI of soft metal for forming a seal between said tubular portionand the tooth.

16. In a syringe, in combination with acylinder and plunger, means Jformoving' the plunger directly against the liquid to compress it in thecylinder. and means for automatically holding said plunger in suchposition.

17. In a syringe, in combination with a cylinder and plungeigmeans formovingsaid plunger step by step to compress the liquid in the cylinder,and means 'for automatically holding said plunger in such position aftereach movement thereof.

18. A point for a syringe having' a central tubular portion, a easing'therefor ot' soft material, and a jacket for said casing'.

19. In adevice Jfor compressinga liquid into a tooth, in combinationwith compressing` means, of a point having a tubular center with acoating' of soft material for forming' a seal between said tubularportion and the tooth, and a jacket for said coating.

In testimony whereof 1 hereunto aliix my signature in the presence oftwo witnesses.

SAMUEL M. 1V EAVER.

Vitnesses:

C. F. SMIEDEL, B. 1V. BuoeiinTT.

